<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        div {
            height: 400px;
        }
        .left {
            float: left;
            width: 150px;
            background-color: green;
        }
        .right {
            float: right;
            width: 300px;
            background-color: blue;
        }
        .middle {
            background-color: pink;
            overflow: hidden;
        }
    </style>
</head>
<body>
    <div class="left"></div>
    <div class="right"></div>
    <div class="middle"></div>
</body>
</html>